Fuel pressure release:
Tool required: J34730-1 Fuel Pressure Gauge or equivalent.
1. Disconnect the negative battery cable, to avoid fuel pump turn on, if an accidental attempt is made to start the engine.
2. Loosen the fuel filler cap to relieve tank vapor pressure.
3. Connect the fuel pressure gauge to the pressure connection. Wrap a shop towel around the fitting while connecting the gauge to avoid spillage.
4. Install bleed hose into an approved container and open the valve to bleed the system pressure. Fuel connections are now safe for servicing.
5. Drain any fuel remaining in the gauge into an approved container.
When repair to the fuel system has been completed, START the engine and check all connections that were loosened for leaks.
Is it needed? If the vehicle has been sitting for a few hours, probably not. If it was recently running, I would.